Re: What would it take....

From:

Da Zheng

Subject:

Re: What would it take....

Date:

Wed, 23 Dec 2009 09:35:03 +0800

User-agent:

Thunderbird 2.0.0.23 (Macintosh/20090812)

Hi,
Samuel Thibault wrote:
>> When process-shared semaphores and mutexes themselves are in the shared
>> memory, can we not use the similar implementation as the ones in the same
>> process?
>
> The implementation uses Mach messages, so it's basically the same thing.
> With different tasks, you need to add the task name along the port name.
> And you need that to be done securely, including for a semaphore between
> a root process and a user process. In a process of a single user, much
> less issues happen.
I didn't realize there is a security issue.
Then must process-shared semaphores and mutexes be implemented in shared
memory? or it's completely through IPCs?
Zheng Da